Cholangiocarcinoma (bile duct cancer) is the most common malignancy of the biliary tract, and is increasing in incidence and mortality worldwide. It is usually diagnosed at an advanced stage, at which point the overall prognosis is poor. However, patients with early stage tumors who undergo resection have excellent outcomes. Conversely, lesions of biliary intraepithelial neoplasia (BilIN), a type of cholangiocarcinoma, frequently appear as indeterminate biliary strictures, and because of the difficulty obtaining enough human tissue for histological analysis, clinical diagnosis is often inconclusive. As a result, a large fraction of patients undergo major surgery only to find that the strictures are benign, or wait too long to have curative surgery. The goal of the collaboration is to develop an image-based diagnostic method that uses fluorescently stained probes and a novel endoscopy device to map the probes. With this method, the time to cancer detection could be reduced and the accuracy of diagnosis improved in the following ways: Quantitative mapping of biomarkers of the biliary epithelium is expected to enable detection of molecular changes before structural changes are apparent - it should improve the ability to distinguish cancer from nonlethal disease, and it may be able to identify molecular targets for cancer therapy. High-contrast fluorescence molecular probes can also be used to image the entire indeterminate biliary stricture and can be used to guide biopsy. Because the molecular biology of cholangiocarcinoma is highly heterogeneous, a method of detecting multiple molecular targets is needed. The researchers will use multiple probes known to bind with different cancer targets and, from an existing prototype, will develop a multimodal multispectral scanning fiber endoscope (mmSFE) capable of wide-field imaging of the fluorescence probes. The probes will be optimized and validated, and the mmSFE will be tested with the validated probes in vivo in mice. After the mouse studies, the mmSFE will be tested in pilot human subject trials using topical application of the fluorescence molecular probes and minimally invasive endoscopy. Quantitative tests will also be performed with ex vivo human tissue and phantom pancreatobiliary organs. In vivo and ex vivo images will be compared with pathology findings in order to develop image-based diagnostic tools that can be used alone or combined with tissue and cell samples. Recent research indicates that methods developed for early detection of biliary cancer will be applicable to cancers of other pancreatobiliary organs, specifically cancer of the pancreas, and the fourth leading cause of cancer deaths in the United States. This project has the long-term potential to reduce late-stage diagnoses of pancreatobiliary cancer, thereby improving prognoses, as well as to reduce overdiagnosis of indeterminate biliary strictures, thereby preventing unnecessary major surgery and trauma.